The present invention relates in general to a microprocessor system particularly one employing dual processors. In a preferred embodiment, the system of this invention is a 16-bit machine and for 16-bit operation, one of the processors is dedicated to input/out tasks while the other processor is dedicated to high-level language tasks. More particularly, the invention pertains to the inter-operation between these processors. One aspect of the present invention is concerned with the boot-up procedure for activating the processors depending upon whether the operating system, normally entered from a disk or diskette, is for an 8-bit or 16-bit machine.
It is an object of the present invention to provide an improved dual processor system having an improved technique for processor operation, particularly at power-up or reset.
Another object of the present invention is to provide a co-processor combination including a 16-bit processor and an 8-bit processor and in which the 8-bit processor is booted up first with the operating system being tested to determine whether or not it is necessary to at all enable the 16-bit processor.
A further object of the present invention is to provide a boot-up procedure in accordance with the preceding objects and which enables the 8-bit processor to turn on first to thus initially make the system appear as an 8-bit system. This has the advantage of making the usual 16-bit machine compatible with 8-bit software written for an 8-bit machine even though the system is normally operated as a 16-bit machine. This feature allows the purchaser to move easily from an 8-bit machine to a 16-bit machine without having to reprogram all operations during the transition.